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21.
Shin-ichiro Nitta Mari Hashimoto Yasuhiro Kazuki Shoko Takehara Hiraku Suzuki Mitsuo Oshimura Hidetaka Akita Kan Chiba Kaoru Kobayashi 《The AAPS journal》2018,20(3):61
Cytochrome P450 3A (CYP3A) enzymes metabolize approximately half of all drugs on the market. Since the endogenous compounds 4β-hydroxycholesterol (4β-HC) and 25-hydroxycholesterol (25-HC) are generated from cholesterol via CYP3A enzymes, we examined whether the plasma levels of 4β-HC and 25-HC reflect hepatic CYP3A4 activity by using a CYP3A-humanized mouse model, in which the function of endogenous Cyp3a was genetically replaced by human CYP3A. CYP3A-humanized mice have great advantages for evaluation of the relationship between hepatic CYP3A protein levels and plasma and hepatic levels of 4β-HC and 25-HC. Levels of CYP3A4 protein in the liver microsomes of CYP3A-humanized mice were increased by treatment with pregnenolone-16α-carbonitrile, a CYP3A inducer. Hepatic and plasma levels of 4β-HC and 25-HC normalized by cholesterol were significantly correlated with hepatic CYP3A4 protein levels. In addition, in vitro studies using human liver microsomes showed that the formation of 4β-HC was strongly inhibited by a CYP3A inhibitor, while the inhibitory effect of the CYP3A inhibition on the formation of 25-HC was weak. These results suggested that CYP3A mainly contributed to the formation of 4β-HC in human liver microsomes, whereas other factors may be involved in the formation of 25-HC. In conclusion, the in vivo studies using CYP3A-humanized mice suggest that plasma 4β-HC and 25-HC levels reflect hepatic CYP3A4 activity. Furthermore, taking the results of in vitro studies using human liver microsomes into consideration, 4β-HC is a more reliable biomarker of hepatic CYP3A activity. 相似文献
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Hiromi Hoshi Atsushi Takagi Shoko Uematsu Kyomi Ashihara Nobuhisa Hagiwara 《Heart and vessels》2014,29(3):300-307
Noninvasive detection of left main/three-vessel diseases (LM/3VD) among patients with non-ST-elevation acute coronary syndromes (NSTEACS) has been difficult using echocardiography. However, two-dimensional (2D) strain/strain-rate analysis is more sensitive in quantitatively assessing contractile abnormality. Accordingly, we aimed to clarify the usefulness of 2D strain/strain-rate analysis for risk stratification of NSTEACS. A total of 50 patients with NSTEACS underwent echocardiography and coronary angiography. We evaluated global longitudinal peak strain (global PS), peak systolic strain rate (global SSR), early diastolic global peak strain rate (global ESR), time from aortic valve closure to peak strain (TAVC-global PS), and global ESR (TAVC-global ESR) in apical four-, two-, and three-chamber views. Patients were divided into two groups according to coronary angiographic findings, the high-risk group (n = 15) with either of left main or three-vessel disease, and the low-risk group (n = 35). There were no significant differences in global SSR and global ESR between the two groups. The amplitude of global PS was significantly reduced in high-risk patients with LM/3VD in comparison with low-risk patients (?17.5 ± 2.4 % vs ?19.8 ± 2.7 %, P = 0.007, respectively). TAVC-global PS and TAVC-global ESR were significantly prolonged in high-risk patients with LM/3VD in comparison with low-risk patients (15.3 ± 25.7 ms vs ?36.8 ± 32.7 ms, P < 0.0001 and 162.8 ± 32.7 ms vs 135.7 ± 41.5 ms, P < 0.03, respectively). Receiver-operating characteristic analysis demonstrated that TAVC-global PS most strongly detected high-risk patients with sensitivity of 100 % and specificity of 74.3 % (area under the curve = 0.938, 95 % confidence interval 0.832–0.986, P = 0.0001). Temporal analysis of 2D strain appeared to be useful in detecting high-risk patients with LM/3VD among patients with NSTEACS. 相似文献
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Nigel P. Field Judith Strasser Sopheap Taing Shoko Horiuchi Sotheara Chhim Wendy Packman 《Psychiatry research》2014
This study addressed the validity of the prolonged grief (PG) construct in a Cambodian context. Eighty mothers who lost a young adult daughter stemming from a crowd stampede incident during the annual water festival were interviewed at the six-month post-loss point along with a control group of similarly aged women who were not recently bereaved. Both groups were assessed for PG, PTSD, anxiety, and depression symptoms and well as for the number of distal losses experienced during the Khmer Rouge (KR) regime – knowing that all the women were old enough to have lived through the KR regime. Support for the discriminant validity of PG was shown in a factor analysis in which its core symptoms were distinguished from anxiety, depression, and PTSD symptoms. Also, support was found for its incremental validity as shown in the unique sensitivity of PG in distinguishing the two groups when controlling for the other symptoms. Lastly, a positive relationship was found between the number of distal deaths experienced during the KR regime and PG symptom severity among the group of recently bereaved mothers, providing support for the predictive validity of PG. Implications as well as study limitations are discussed. 相似文献
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Chris Fook Sheng Ng Kayo Ueda Ayano Takeuchi Hiroshi Nitta Shoko Konishi Rinako Bagrowicz Chiho Watanabe Akinori Takami 《Journal of epidemiology / Japan Epidemiological Association》2014,24(1):15-24
Background
Ambient temperature affects mortality in susceptible populations, but regional differences in this association remain unclear in Japan. We conducted a time-series study to examine the variation in the effects of ambient temperature on daily mortality across Japan.Methods
A total of 731 558 all-age non-accidental deaths in 6 cities during 2002–2007 were analyzed. The association between daily mortality and ambient temperature was examined using distributed lag nonlinear models with Poisson distribution. City-specific estimates were combined using random-effects meta-analysis. Bivariate random-effects meta-regressions were used to examine the moderating effect of city characteristics.Results
The effect of heat generally persisted for 1 to 2 days. In warmer communities, the effect of cold weather lasted for approximately 1 week. The combined increases in mortality risk due to heat (99th vs 90th percentile of city-specific temperature) and cold (first vs 10th percentile) were 2.21% (95% CI, 1.38%–3.04%) and 3.47% (1.75%–5.21%), respectively. City-specific effects based on absolute temperature changes were more heterogeneous than estimates based on relative changes, which suggests some degree of acclimatization. Northern populations with a cool climate appeared acclimatized to low temperature but were still vulnerable to extreme cold weather. Population density, average income, cost of property rental, and number of nurses appeared to influence variation in heat effect across cities.Conclusions
We noted clear regional variation in temperature-related increases in mortality risk, which should be considered when planning preventive measures.Key words: heat, cold, mortality, time-series, distributed lag 相似文献26.
Masahiro Ohira Yasuhiro Watanabe Takashi Yamaguchi Hiroki Onda Shuhei Yamaoka Kazuki Abe Shoko Nakamura Sho Tanaka Naoyuki Kawagoe Taiki Nabekura Takashi Oshiro Daiji Nagayama Ichiro Tatsuno Atsuhito Saiki 《Obesity facts》2021,14(6):633
IntroductionLaparoscopic sleeve gastrectomy (LSG) significantly increases high-density lipoprotein cholesterol (HDL-C) and lipoprotein lipase (LPL) in pre-heparin serum (pre-heparin LPL levels). LPL is a regulator of serum triglyceride (TG) and HDL-C production; this may be the mechanism for HDL-C increase after LSG. This study aimed to elucidate the mechanism of increase in HDL-C levels by examining the relationship between changes in serum HDL-C levels and LPL after LSG.MethodsWe retrospectively reviewed 104 obese patients, who underwent LSG and were followed up for 12 months. We analyzed the relationship between changes in serum HDL-C levels and various clinical parameters after LSG.ResultsA significant decrease was observed in the patients'' BMI and serum TG levels after LSG. Conversely, HDL-C levels and pre-heparin LPL levels were significantly increased after LSG. Simple linear regression showed that changes in HDL-C levels were significantly correlated with total weight loss percentage, change in TG levels, abdominal fat areas, and pre-heparin LPL levels. Additionally, the multiple regression model revealed that a decrease in TG levels and an increase in pre-heparin LPL levels were correlated with increased HDL-C levels after LSG.Discussion/ConclusionThese results show that a decrease in TG levels and an increase in LPL are mechanisms for increased HDL-C levels after LSG. 相似文献
27.
Minoru Hoshiyama Yoshihiro Kitamura Sachiko Koyama Shoko Watanabe Motoko Shimojo Ryusuke Kakigi 《Muscle & nerve》1996,19(2):125-131
Reciprocal change of motor-evoked potentials (MEPs) recorded from the agonist and antagonist muscles of the forearm was studied in 10 normal subjects in whom transcranial magnetic stimulation (TMS) was applied to the hand motor area before voluntary wrist movements. MEP recorded from the agonist muscles, that is, radial extensor muscles for wrist extension and ulnar flexor muscle for wrist flexion, were gradually facilitated with shortening of the interval between the magnetic stimulation and the voluntary muscle contraction. In contrast, MEP recorded from the antagonist muscles, that is, ulnar flexor muscle for wrist extension and radial extensor muscles for wrist flexion, were gradually suppressed as the interval shortened. The reciprocal change of MEP was recognized when TMS was applied within 60 ms prior to the voluntary movements. The present data confirmed that reciprocal change of MEP was recognized before voluntary movements; they further suggest that cortically originated reciprocal control of the corticospinal pathway may exist and that it may be generated just before the voluntary movement. © 1996 John Wiley & Sons, Inc. 相似文献
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Hitomi Sakurai Mitsuaki Suzuki Shoko Itakura Hiroaki Todo Florencio Arce Jr. Gerard Lee See Takashi Tanikawa Yutaka Inoue 《Materials》2022,15(8)
Ellagic acid (EA), a natural polyphenol found in berries, has high antioxidant capacity. This study aimed to improve EA solubility by complex formation with urea (UR) using solvent evaporation method and evaluate its solubility, antioxidant capacity, and physical properties. The solubility test (25 °C, 72 h) showed that the solubility of EVP (EA/UR = 1/1) was approximately two-fold higher than that of EA (7.13 µg/mL versus 3.99 µg/mL). Moreover, the IC50 values of EA and EVP (EA/UR = 1/1) (1.50 µg/mL and 1.30 µg/mL, respectively) showed higher antioxidant capacity of EVP than that of EA. DSC analysis revealed that the UR peak at 134 °C disappeared, and a new endothermic peak was observed at approximately 250 °C for EVP (EA/UR = 1/1). PXRD measurements showed that the characteristic peaks of EA at 2θ = 12.0° and 28.0° and of UR at 2θ = 22.0°, 24.3°, and 29.1° disappeared and that new peaks were identified at 2θ = 10.6°, 18.7°, and 26.8° for EVP (EA/UR = 1/1). According to 2D NOESY NMR spectroscopy, cross-peaks were observed between the -NH and -OH groups, suggesting intermolecular interactions between EA and UR. Therefore, complexation was confirmed in EA/UR = 1/1 prepared by solvent evaporation, suggesting that it contributed to the improvement in solubility and antioxidant capacity of EA. 相似文献